how to delete empty line form variable?

hi,
Does anybody know how to manipulate string variable so that it would remove empty line from the end of variable.

the situation is the following:
i pop the end of line from cmd line, but since i don't know it's end's exact lenth, i have to use following code(it's lenth is not more than 10 characters):

 Pop $0
 strcpy $1 $0 10 30
 ;select up to 10 characters from postiton 30 

now the $1 has string in it, with empty line in the end of it.
I need to put it into text file, and i don't like empty line in the end of this string.

Use the TrimNewLines function from the documentation.

tnx